There is a need to provide consumers with video services on-demand. Desirable video on-demand services can include, for example, movies, sporting events, interactive games, home shopping, textual information, and educational and arts programs, hereinafter collectively referred to as "videos". It should be understood that videos generally includes both video and audio portions, although, a video may only have an image portion as in textual information, or only an audio portion, as for example music.
Consumers would like videos of their choice to be available at times and locations convenient for them. It would be an advantage if the videos could be delivered by any transmission medium, such as commercial telephone, cable, and satellite networks. The videos should be compatible with readily available display systems, such as NTSC standard televisions, or personal computers.
Furthermore, consumers would like to have real-time, interactive VCR-like control of the videos, skipping, holding, or replaying portions at will. Home shopping and video games require a much higher level of interaction between the video and the game-player. In addition, the system used to provide video on-demand services should be scaleable at a reasonable cost to maximize the availability of the service to large populations of consumers.
A major problem with known distribution systems for video services, such as broadcast or cable television is that the consumer has no control over program or time selection. Also, known video distribution systems are limited by predetermined channel allocations in the number of different videos that are available at any one time. And, most known video services are generally not interactive.
Some video services allow for on-demand delivery of videos over specialized high-speed fiber optic cable networks. Generally such services deliver the video to the customer as one continuous uninterruptable stream. Therefore, such services generally require expensive mass storage devices and special play-back equipment at the consumer's location to provide interaction. Alternative such services require duplicate system resources at the distribution site for each of the customers, even if multiple customers are viewing the same video. Consequently, known video on-demand systems which deliver videos to consumers are not easily expandable to large scale distribution.